Answer:
<em>The car will be moving at 5.48 m/s at the bottom of the hill</em>
Explanation:
<u>Principle of Conservation of Mechanical Energy</u>
In the absence of friction, the total mechanical energy is conserved. That means that
is constant, being U the potential energy and K the kinetic energy
U=mgh
When the car is at the top of the hill, its speed is 0, but its height h should be enough to produce the needed speed v down the hill.
The Kinetic energy is then, zero. When the car gets enough speed we assume it is achieved at ground level, so the potential energy runs out to zero but the Kinetic is at max. So the initial potential energy is transformed into kinetic energy.
We are given the initial potential energy U=45 J. It all is transformed to kinetic energy at the bottom of the hill, thus:
Multiplying by 2:
Dividing by m:
Taking square roots:
v = 5.48 m/s
The car will be moving at 5.48 m/s at the bottom of the hill
Number three. How water evaporates and then forms rain and snow.
The following are the answers to
the questions presented:
<span>1.
</span>Mechanical Advantage =
95 ⁄ 15
MA = 6.33
2.
The
wheel-and-axle principle.
I am hoping that these answers
have satisfied your queries and it will be able to help you in your endeavors, and
if you would like, feel free to ask another question.
<span>Answers: (a) 2.0 m/s (b) 4 m/s
Method:
(a) By conservation of momentum, the velocity of the center of mass is unchanged, i.e., 2.0 m/s.
(b) The velocity of the center of mass = (m1v1+m2v2) / (m1+m2)
Since the second mass is initially at rest, vcom = m1v1 / (m1+m2)
Therefore, the initial v1 = vcom (m1+m2) / m1 = 2.0 m/s x 6 = 12 m/s
Since the second mass is initially at rest, v2f = v1i (2m1 /m1+m2 ) = 12 m/s (2/6) = 4 m/s </span>
Answer:
The temperature of the windings are 60.61 °C
Explanation:
Step 1: Data given
Resistance = 50 Ω
Temperature = 20.0 °C
After the motor has run for several hours the resistance rises to 58Ω.
Step 2: Calculate the new temperature
Formula: R = Rref(1 + α(T-Tref))
⇒with α = temperature coëfficiënt of Cupper at 20 °C = 0.00394/°C
⇒with Tref = reference temperature = 20°C
⇒with T = end temperature = TO BE DETERMINED
⇒with R = resistance at end temperature = 58Ω
⇒with Rref = resistance at reference temperature = 50 Ω
==> T = (R/Rref - 1)/α + Tref
T = (58/50) - 1 )/ 0.00394 + 20
T = 60.61 °C
The temperature of the windings are 60.61 °C
